A majority of laser diode driver integrated circuits (ICs) for optical transmission can be broadly divided into two categories. The first category includes devices using direct modulation. This is generally used for short distance transmission in which a laser diode driver IC is used to directly drive a laser diode module with a drive current supplied by the laser diode driver IC. The second category includes devices which generally use external modulation. These are commonly used for long-distance transmission in which, for example, an electroabsorption (EA) modulator driver IC is used to drive an electroabsorption (EA) modulator module. In both of these categories, laser diode driver ICs can be found in both die forms in which the IC is assembled inside the laser module, and in packaged forms in which the IC is assembled outside of the laser module and connected by a transmission line.
Due to the need for ever increasing data transmission rates, the use of conventional laser diode driver integrated circuits results in numerous signal quality problems. In addition, convention laser diode driver integrated circuits consume a high amount of power due to the need for high supply voltages. Thus there is a need for laser diode driver integrated circuits that provide improved output signal quality as well as lower power consumption.